In 2006, a construction sites for relocating some water pipe lines in Hong Kong led to a discovery of 8 skeletons (1 adult and 7 children, according to all local news reports). The locals, especially those from one generation older immediately thought this was linked to this spooky old belief.
這邊的問題很多：（1）無超過十歲？（2）死了十年以上？（3）為甚麼疊在一起？但這次，我想先簡述第一個問題：如何決定小孩子骸骨沒有超過十歲。 Continue reading
由於跌倒，本能反應是以雙手先撐地，而有機會造成手腕骨折。藉著這則新聞，就向大家介紹一下最常見的（手腕）骨折：橈骨末（／遠）端骨折 (Colles’ Fracture/ Distal Radius Fracture)
Q: what do we do with unknown or unidentified remains from the morgue, or those excavated from exhumation?
A: we clean them by a process called maceration. When forensic anthropologists come into the scene,these remains are most likely in advanced decomposition stage (usually most of the soft tissues are gone), we need to clean the remaining attached soft tissues before doing examination or identification. This process is called maceration (which is no different than the maceration we know in food preparation- sorry if I just ruined your meals :(. #sorrynotsorry ) anyways, these usually can be done by either having forensic anthropologists handpick the attached tissues with tweezers or other tools. They have to be careful that the tools may leave marks on the bones. They have to remove as many soft tissues as they can during this process. This process usually starts by dismembering the remains. Or, we can ask our lovely bugs friends- beetles for help by inviting them to this feast. They will usually focus on the tissues only without damaging the bones. After all of these are done, bones are being boiled in a big pot filled with detergent like bleach, soap and water. Cook the bones for a while, and drained it. In research institutes or in morgues, these cleaned bones will be stored in a long shoe box for storage until someone can give them a positive identification, or reclaim them.
Last thought: can u imagine we all can reduce into a size of a shoe box only at the end of the day? Sighhh…
Skull is one of the most cliché symbols. It represents both power and mortality and has been preserved for scientific and artistic purposes. It is very important in terms of forensic anthropology to tell the biological profile of the deceased: sex, age, and ancestry. And on the other hand, it has significant yet different meaning in cultures. In other words, skull or head sometimes symbolizes as a person, and sometimes merely as a thing. In this following entries, together with the next, I will endeavor to illustrate and discuss the meanings of skulls from biological anthropology and cultural anthropology.
Let’s begin with the anatomy of a skull.
Skull composed of 22 visible bones (3 ear ossicles on each side are not counted). Other than the mandible (the lower jaw), these bones are tightly articulate at the suture line. As a person aged, the suture lines will fuse together, and thus keep bones in place. Skulls are widely studied by scholars, thus divided into four topical areas: bones, sinuses, landmarks and sutures. We are going to look at them one by one in brief:
As mentioned above, it is the lines where the bones of the skull meet and fuse together in the later stage of one’s life. Some sutures would even completely obliterated in old age, which is definitely a feature to help determine age of deceased.
Sinuses refer to the pockets of air within sections of some of the cranial bones. The frontal sinus is an open area that lies above the upper boarder of the eye orbits, as well as the lower portion (towards nose) of the frontal bone. Maxillary sinuses are other larger sinuses in the upper jaw. Research has it that frontal sinuses in particular are unique enough for getting positive identification by comparing with antemortem (before death) radiographs.
These are the measuring reference points for measurement or description purposes.
Speaking about bones, I would like to focus on how anthropologist use skull to sex and determine ancestry from the anthroposcopic characteristics. First for sexing, including the overall size of the skull, there are 6 traits anthropologist would look for when sexing with the skull: mastoid process, nuchal crest, supra-orbital margin, supra-orbital ridge, and mental eminence.
- Mastoid Process: Male exhibits larger (and fatter) mastoid process when compares with females
- Overall size: Male skull is larger in size and more robust, and usually with more prominent and pronounced features
- Nuchal crest (or, the hook at the back of one’s head) : Male usually comes with a rugged nuchal area with inion hook, while female usually has a smoother nuchal area and the inion hook is absent.
- Supra-orbital margin (the margin of the upper eye socket): Males usually have more rounded and smooth margin, whereas female exhibits a sharper and pointy margin in comparison.
- Supra-orbital ridges: Male has a more pronounced ridge, where female has less pronounced or absent of ridges
- Mental eminence on the lower jaw: Male usually observed with a more squared chin, while female is usually observed with a more pointed one.
For ancestry estimation, anthroposcopic traits are the main way for ancestry classification. Yet, traits are categorized by gradation, and thus the ambiguities make ancestry as the most difficult attributes to be made.
These days, differentiations are no longer obvious as above. It mostly relied on the sense of touch when the osteologist or anthropologist feel and “communicate” with the bones. Also, anthropologists would never solely determine a biological profile component from one characteristic. Rather, they would gather as much info as possible from the skeleton in order to make the estimation more accurate.
Byers, Steven N.. (2011). Introduction to Forensic Anthropology. 4th edition. Upper Saddle River: Prentice Hall, Chapter 7-8.
Trauma affects the skeleton via fracturing and dislocating the bones, which would disrupt the blood and nerve supply. Studying the osteological trauma can possibly tell the violence happened. There are three types of fractures: traumatic fracture, pathologic fracture, and periprosthetic fracture. Among these, we are going to discuss traumatic fracture, particularly from projectile trauma here with reference to the real case I encountered in the morgue.
The deceased was a male, in late twenties or early thirties. He expired at 6 am and two hours later, he is with us in the morgue. According to the death investigator back from the crime scene, he attempted to kill his girlfriend and suicide. His girlfriend survived, but not him.
Externally, there is one bullet hole on each side of the skull. According to the external condition, it is possible that the wound on the right would be the entrance wound, and the left would be the exit wound. Yet, it is the otherwise when we have shaved his hair and opened up the skull.
After shaving his hair however, the beveling is really clear. Judging from the projectile fracture and the beveling, the exit wound would be on the right and the entrance would be the wound on the left.
Trajectory of the projectile, usually gunshot wounds, can be located and identified as either penetrating when no exit wound is found, or perforating that a projectile has an entrance and exit like the captioned case. Crime investigation unit will usually use color stick to link the trajectory for verification. Speaking of beveling, a skull contains layers—inner and out table. The force of the projectile would impact differently on the layers, and caused differences performances on entrance and exit spot. Generally speaking, when a bullet enters it produces a sharp-edged on the outer surface of the skull, but “beveled-out” on the inner surface, and this is called internal beveling.
Internal beveling (Source: the University of Tennessee, Department of Anthropology)
External beveling is usually seen on the exit wound—the outer surface beveled out. Yet occasionally would also be seen on the entrance site, depends on the way of holding the projectile and the distance of the projectile from the head. There is also one condition called the keyhole, which would only be seen when the entrance and exit wound overlapped.
External beveling (Source: the University of Tennessee, Department of Anthropology)
Keyhole wound (Source: the University of Tennessee, Department of Anthropology)
So, the entrance wound for this case is on the left and the exit on the right, does it mean the deceased is left-handed? According to the M.E., he stated that there are indeed studies done and show that no relevance with hand preferences to pull the trigger.
The M.E. also pointed out that sometimes blunt force and projectile force trauma may not directly fatal. The energy from the trauma could be transmitted and make the brain tissue hit on the foramen magnum that creates a second wave of trauma. That would delay the death a little.
Also, on the other case that another M.E. was working on, they found negative results from autopsies on cause of death. They found only hemorrhage in his brain but the skull did not fracture at all. He decided to open up the deceased at the back and see if they can trace fractures, possibly compression fracture on the neck and the spine that would cause instant death, and the autopsy later confirmed this manner of death.
Every beginning of a week in the Medical Examiner Office is the busiest, as the bodies came in throughout the weekend are all lined up for check-out check and autopsies on Monday. Also, a lot of parties going on, especially in Miami every weekend, young adults accidentally died from overdose, drunk drive and so on could happen more easily. Of one of the particular Monday, among the 5 cases that came in, there were two really remarkable ones.
Both of the cases are having young deceased individuals, with one female and one male respectively. The female was expired from a car accident, where the male was suffered nasal congestion suddenly and expired.
What really fascinating (I know this might sound inappropriate, apologize for that. Fascinating from the medical and forensic fashion,) is the stitches on both deceases’ limbs. We were told that some of their limb bones are taken out for bone donation. I have never thought about bone donation before (sorry for my ignorance). According to one of the morgue technicians, those fresh and healthy bones for “transplant” have to be removed within a day from the deceased since the heart stopped beating. After taking out the bones for donation, they would stuff towels back into the limbs and sew it up. The limbs do not look any differences, nor feel any differences when you first touch it. But when the morgue technician was trying to clean them lifted their limbs up and twisted it. The difference is huge!
Who can donate bones?
According to the Musculoskeletal Transplant Foundation, majority of bone donors were health and relatively young deceased who died in accidents, or sudden illness (heart attack or stroke). Screenings including medical histories and social histories (location of any high-risk behaviors for transmissible diseases will automatically eliminate from the pool for possible donation). Potential donors with histories of any condition that would affect long-term bone performance would also be excluded.
Bone donation counted as tissue donation. Unlike organ donation, tissue recipients do not have to match with the donors, as rejection is not the mainly concern. Organ donation donors are basically brain dead, and the donation process occurs when mechanical support that continue the organs to “live” for an extended short period of time after the death of the patient. Organ donation needs patience, as it requires matching blood type, medical status and so forth, whereas tissue donation only requires patients to be brain dead or cardiac death.
Also, for the lady who expired from the accident, she did not have any trauma in her body except for few broken ribs (which could possibly hurt her lungs), suspecting she might have been drink and drive. Her major blow was the blunt force trauma on her left posterior temple bone. The blow was so strong that the energy transmitted all across the occipital bone and reached the right temple bone, as well as fractured the base of the skull too. It gives me goose bumps. I hope that the blow did not kill her slow! The brain did not look abnormal except being bloody. The Medical Examiner says the blow could have done some traumas on the brain (yet we did not get to see the cutting of the brain today), but that amount of blood was sufficient to make her choke and swallow her own blood and caused aspiration on her lungs. Doctor says the blow should have her killed pretty quickly but may slow down due to the aspiration.
One personal thought:
I think if the government used the traumas and the fractures as warning for “Do not drink and drive” commercials would be working more effective than ordinary movie clips. This lady’s traumas definitely warn me more effectively to stay out of alcohol if I am driving.
We are all dead.
We have exhaled the last breath. Our heart has stopped pumping blood for the brain and the body. We died.
Unfortunately, no one was with us when that moment came until now. Will the coroner and the medical examiner know when that particular moment happened? Yes.
How? They have the interval detectives.
Upon the discovery of human remains, the key question asked usually was the time of death. To answer that question, M.E. has to find out the postmortem interval (PMI), which is the amount of time has elapsed since the death.
Photo illustration by James Emmerman. Photo by Shutterstock
There are ways to do so. Recalling the decomposition schedule we discussed last time, in the first few hours, a lot of changes would happen: livor mortis (settling blood, algor mortis (cooling of body temp) and rigor mortis (stiffness). These methods usually able to accurately calculate the first, at most 24 hours interval. By the time the body starts decomposing, these would not work.
A lot of Medical Examiner would choose to use the drop of body temperature as a tool to get PMI. Average body (living body) temperature is about 37⁰C or 98.6⁰F. Under normal circumstances, at normal room temperature, the body would drop 1.5⁰C in the first hour after death, and between 1.5 and 1⁰C every hour after that, and stopped until it reached the room temperature. By comparing and calculating, it would allow the M.E. find the time of death. Yet, it does not work at best when the body starts decomposing.
A number of factors will affect the rate of the temperature drop. A naked body will be at a faster rate than a body that is wrapped like a gift. Also, body of lesser weight will enjoy the privilege of faster temperature drop too! If the body has been dead for days, looking into the past weather reports would help too.
Seems like everything does not work as well when the decomposition begins. Correct! But we are so lucky that the mother nature gives us our little death detectives– insects!
The application of insects or bugs science to investigation about crimes is called forensic entomology. Entomology, means the study of insects. The live and dead insects found at the site of crime can tell many things, from the crime scene, the length of time the body had been there, the time since death, and even if the victim being drugged.
After the rigor mortis is over, putrefaction begins. It is about the internal breaking down of the proteins in a decomp body. Acid like the gastric juice (Hydrochloric acid) starts eating the internal organ, releases gases (ammonia, nitrogen, carbon dioxide, and methane). They sometimes bloats the body cavity. As the decomposition goes, the odor would get stronger. That’s the odor cadaver dogs rely on to look for a body. Lately, an international research team measured the volatile organic compounds (VOCs) from pig carcasses, they identified a cocktail of several families of molecules. The found that the combination and quantities of the VOCs change as the body go through stages of decomposition. It worked as the “odor fingerprint” of decomp.
Insects then, particularly flies, begin feeding on remains. Studies show that flies are attracted by the released gas, and have a feast around the moist and opened tissues/ areas: eyes, ears, nose, mouth, vagina, penis, anus. If there are wounds (antemortem and perimortem), they would invite themselves into these areas too. As they continue to enjoy the feast, they reproduce. The deposit eggs in and around the remains, and starts a cycle of arthropod activity. The schedule is as follows (Bass 1977):
- First Day: Egg masses of insects (may look like white sawdust); veins seen through skin may be blue or dark green; body fluid may be present around nose and mouth.
- First Week: Maggots are active on the face; bones around eyes and nose may be exposed; beetles may appear; skin and hair may slip from the body; remains emanate odor of decay; abdomen may be bloated; molds may begin appear on the skin; animals may be active. VOCs or Volatile fatty acids may killed the vegetation in area around the body.
- First Month: Maggot activity less, beetles more common; no more bloating. Bones will be expose if the body is shaded. Skin may be leathery if its exposed to sunlight, which protects the maggots from the sun. Mammalian carnivores may appear and remove body parts; molds can be found; adipocere (Grave Wax) may be present.
- First Year: Skeleton fully exposed and bleached; moss and/or green algae may be growing on shaded bones. rodent gnawing; animals may nest in the skull.
- First decade: Exfoliation of cortical bone may be present; longitudinal cracks may occur in long bones exposed to sun; roots of plants may be growing in or through bones.
“You are what you eat. So do the insects.”
As you may realize by now, the insects are entirely fed on the body. Entomologist by studying the living habit or the life cycle of the insects may be able to tell if the insects have intake some alternative materials from the body, such as necrotic. Likewise, insects can help clean the bones by having them eating up the soft tissue. These are the most convenient way to do if maceration is not on the top of your list.
Other than forensic entomology, forensic botany (the application of plant science to investigation about crimes) is also useful to map out the time elapsed since death. You may recognize in the above schedule, the plant would die out after the first week. The acids from the internal body would kill all the nutrients, acidify the soil, and make the soil is not suitable for plantation. However, later on, when the whole body started breaking down, the whole body is indeed some sort of organic nutrients. The decomposition of body thus can restore the nutrients into the acidify soil. Plants will grow nice and strong at the spot. Thus, abnormal plantation patterns may reflect the placement of dead body too. Plus, plants and roots would grow around the bones (as support sometimes).
A new finding from Forensic Biologist from Switzerland found that the density of testate amoebas in the soil underneath the cadavers help date older corps. The study finds that not one single living amoeba found be found under the cadavers at 22 and 33 days after placement, while only by day 64 the amoebas start to rebound in the soil under the pig. Yet, the level of amoebas did not restore to its normal level (according to the control) even after a year.
Bass, W.M. (1997). Outdoor decomposition rates in Tennessee. In: Halgund, W.D., Sorg, M.H., eds. Forensic Taphonomy. New York: CRC Press.
Byers, Steven N.. (2011). Introduction to Forensic Anthropology. 4th edition. Upper Saddle River: Prentice Hall, pp. 94-111.
Frazer, Jennifer. (2014). “A Surprising Time-of-Death Tool.” Scientific American. September 16, 2014.
Knowles, Ruth. (2014). “Changing Smell of Corpses Measures Time of Death.” Scientific American. June 26, 2014.
One of the “dirty jobs” (I mean stinky and sorta dirty literally) of Forensic Anthropologist is doing maceration. Maceration is the process of getting rid of all the soft tissues, aka tendons, fleshes, muscles, and so on. It includes processes from picking the tissues (requires concentration and focus like you separating types of beans from a big mixing bowl! ), and cleaning the bone with detergent. This usually happens to unclaimed bodies stored in the morgue or randomly found human remains before doing any examinations. And in our case this time, just because the individual has been in the freezer long enough and unclaimed, we need to free up some space. After cleaning, bones are well-documented, and place in a paper box with well-documented details, and stored in the bone room. I can tell you some in the bone room have even preserved the hair (real hair!) and the finger nails.
Decomposing bodies especially those before or suitable maceration usually have stronger odor than the regular dead bodies found in usual autopsy morgue. I was kind of trying to prepare myself for the odor (though did not really know how to!) before entering the decomp autopsy room.
In Cantonese, “salty fish” (haam yu) is a slang term to describe a dead body. “Salty fish” is literally a fish that sautéed in salt and dried under the sun. It was used for preservation in the last decades (it makes fried rice taste better too!). The decomposing body, I assure you, smells exactly the same as “salty fish” to me. And I now understand why the slang came out like so. If you really have no clue, go to the closest chinatown in your place, find a dried seafood stall, and ask if they have salty fish for sell. Take a sniff, it wakes you up better than your morning cup of joe! (But it smells really nice when you made fried rices with diced salty fish and chicken :p nom nom…)
Maceration really fascinates me! The individual I helped handle and macerate is an unknown male, passed away in 2012. He has been autopsied and remained in the Miami-Dade Medical Examiner Department cooler for the past two years. Part of the body of this individual has been mummified. The mummified condition shows profoundly on his skull, mandible, rib cage and his lower legs. The legs are covered with mummified skins with molds on the. What really fascinating is that when we went the scalpel through his upper thighs, flesh in both of the thighs are still fresh red (the left femur though is more brick red, not sure about the reason). It is really interesting that for the body has already sit in a cooler for more than two years but the flesh inside could be still blood red.
Bone room the “playground” of forensic anthropologist, full of unknown remains that are hoping for getting a positive identification to provide closure to the families. Being in the bone room excites me again (which reminds me the first excitement I worked on biological profiling in my Forensic Anthropology class)! Yet, these individuals, especially when we went through some of the cases in the room, make me wonder if their loved ones still looking for them.
As you all may be aware that, every cadaver is bio-hazard. We need full protection. And that’s how we do it:
Cap + double gloves + full coverage surgical mask +scrubs + gown + protection booties = full gear!
Yeeeep! That’s me 🙂 Gearing up!
“I shall fear you with a handful of dust.”-T.S. Eliot.
The fear of death does not come from the death per se, but is the fear that no one will remember you or know you are dead. I think all of these individuals in the bone room once had the same thoughts, and their families deserve an answer.
*You may wish to read about some background on the internship here (Prelude).
What is it?
Literally, it means a farm with bodies. To be precise, it is a farm with dead bodies either donated by the deceased families, or they are the unclaimed bodies in hospitals, or morgues. If zooming in even more, it is a place that has dead bodies freely lied on the ground, in order to study the decomposition process of the cadaver.
The rate of decomposition depends on some environmental factors, for example weather (heat? cold? hot? warm?), humidity, exposure to direct sun lights, etc. The body farm is thus having bodies situated in different combination of the above mentioned elements as part of the research in order to nail the decomposition rate, which essentially help with identify the postmortem interval (the time between time of death and the time until the police got to the scene), and find out the story behind.
In the States there are several body farms, the most well-known one would be the one begun by Dr. William Bass in the University of Tennessee at Knoxville. This facility has dozens of students learning and working inside every year. The other one would be the FreeRanch ran by Texas State University. What makes it really special is that due to the maximized degree of sunlight the facility absorb, the bodies inside the facility usually are being mummified. Most importantly the heat even make the bodies inhospitable for bacterias and insects (flies).
So, what will one see in body farm other than a lot of bodies laying on the ground or in the testing elements?
Pretty much everything really happens after one’s death, but not usually being seen.
Decomposition of dead bodies go through stages. When a person just stopped his/her last heart beat, he will go through 7 stages (in general).
- Pallor mortis/ post mortem palness: usually happens right after death because of the lack of blood circulation through out the whole body. The red blood cells then will sink, and caused,
- Livor mortis: It can happen from twenty minutes to few hours after death, and continued for few hours. Basically, the red blood cells are pulled by the gravity, where the pressured point (contacting point with another object, be that may a table, a hand etc) will be discolored. The pattern of livor mortis can tell the M.E. about the position of death, and know if the body has been moved.
- Algor mortis: drop of body temperature. Theory has it that the body temperature will drop in a constant rate till it matches with the room temperature (the first hour will drop 2°C and thereafter 1°C per hour) By doing a simply mathematics calculation, the M.E. will be able to calculate the number of hours since the heart has stopped.
- Rigor mortis: Stiffness of muscles. It usually begins after about three hours, and will become soft again after 24 hours of death.
- Putrefaction: It is about the internal breaking down process of the proteins in a decomp body. Not long after the heart stopped, the bacteria in the body (e.g. digestion system) breakdown the cohesion between tissues and organs. Of course, this comes with a very unique odors.
- Decomposition: living organisms decomposed after death. Those wounds, or moist areas/ open areas (for example: eyes, mouth, ears) are usually the first place where the decomposition happens, as well as finding the eggs of flies and maggots. Studies found that areas with tattoos are usually decomposed in a slower rate than the areas without any. The gastric acid released in the process of decomposition would acidify the soil (if it is on the ground) at first, but then will nutritious the soil later on. Thus if police or law enforcement bodies found a weird area with heavy plantation out of nowhere, and a homicide happened around that area before, it could be the spot where the body was buried.
- Skeletonization: IT is the latest stage of decomposition, in which the soft tissues are already dried or decayed.
Other than situating the bodies in the body farms, researchers sometimes would use pig as a substitute of human body to do certain research, for example to study the bones found in a fire. It is because, pigs have similar gastric bacterias and about the same size as human. Lately, there was a study on using pigs to learn about bodies found in the ocean.
The Huffington Post. Dead Pigs Dumped Into The Ocean… For Science!
Stromberg, Joseph. October 28 2014. The science of human decay Inside the world’s largest body farm